I used to feel the same way as Darryl and Tony about Instant Ocean, but having made the change back and forth between IO and H2Ocean 4 times I've noticed a significant change in my reef tanks each time. I won't use IO on my reefs anymore, I've decided IO is for FO tanks only. I haven't used RC on my reefs in many years, but every once in awhile I use it on my FO tanks when I can't get IO. Besides, H2Ocean is natural sea salt - there
has to be a difference using natural sea salt as opposed to synthetic sea salt...there has to be.
